Here are some resources for Zeved Habat/Simchat Bat welcoming a baby girl. This is by no means extensive so feel free to add ideas in comments. Thanks to my friend Rosemary Eshel who shared resources when I was looking for ideas of what to do for our daughter quite a while ago.
In the end we did a siyum. We learned Makot and did a celebratory meal or seudat mitzvah. We did it around Elul (a traditional time for Zeved Habat) when things had settled down a bit.
This is more like a (poor) bibliography. If its useful, enjoy! If you have anything to add, happy to learn new things.
Jewish Women’s Naming Rights and the Rights of Jewish Women Nashim 4 2001:140-177
When Should Baby Girls Be Named? Insight Israel 6:3, November 2005
שפרכר, רחלי זבד הבת
http://www.jofa.org/about.php/publications/orthodoxjewi JOFA manual on birth (pdf)
Itim resources Including some ceremony materials
Tobi Kahn Simchat Bat Ritual Naming Chair (Page 27) Objects of the spirit: ritual and the art of Tobi Kahn ed. Emily D. Bilski
Joel Wolowelsky Jewish Woman
midrash kohelet rabba vii, 3
Isaac Klein “Namegiving”, in A Guide to Jewish Religious Practice (The Moreshet series), New York (JTS), 1979. (Page 429.)
See also http://www.ritualwell.org/lifecycles/babieschildren/babynamingsimchatbat/sitefolder.2005-06-07.6945408008/GiftOfADaughter.xml
Holle’s Cry: Unearthing a Birth Goddess in a German Jewish Naming Ceremony
Nashim: A Journal of Jewish Women’s Studies & Gender Issues 9, Spring 5765/2005, pp. 62-87
שרשי מנהג אשכנז מכון מורשת אשכנז
When the baby is named on shabbat in shul, the congregation sings traditional pizmonim, songs/poems welcoming the baby girl.
Las Fadas A ceremony of Turkish/Balkan Jews. Generally takes place about two weeks after a baby girl is born. It seems to date to medieval Spain. The baby is passed around and given blessings by family and friends.
India: The Baghdadi Jews The Jews of India, India: Bene Israel barsa Naming Ceremony for a girl Israel Museum Catalog 1995:146-148
Symbolic Decorations for a Woman after Childbirth in San’a – Israel Museum Journal 7
Shisha Festival (6th day) Iraqi Jews named baby girls on the sixth day after birth at a sixth day celebration.
Herbert C. Dobrinsky: A Treasury of Sephardic Laws and Customs: the ritual practices of Syrian, Moroccan, Judeo-Spanish and Spanish and Portuguese Jews of North America. Revised edition. Hoboken, NJ (Ktav); New York, NY (Yeshiva Univ. Press), 1988. (Pages 3-29.)
Book of prayer of the Spanish and Portuguese Jews’ Congregation, London. Volume One: Daily and occasional prayers. Oxford (Oxford Univ. Press, Vivian Ridler), 5725 – 1965. (Page 180.)